1. Field of the Invention
The present invention relates to a mechanism for removing a jammed fastener from a fastener drive track formed in a driver guide of a fastener driving device.
2. Description of the Prior Art
A conventional fastener driving device includes a driver guide having therein a fastener drive track through which a driver is reciprocally moved for ejecting fasteners one after another. A mechanism is provided for removing a fastener which has been jammed in the fastener drive track and which cannot be driven by the driver.
Japanese Laid-Open Utility Model Publication Nos. 60-125078 and 60-61179 disclose a mechanism having a guide member forming a part of a driver guide. The guide member is pivotable relative to the drive guide or is detachable from the driver guide. A fastener jammed within a fastener drive track can be removed by pivotally moving the guide member or by removing the same from the driver guide.
Japanese Patent Publication No. 43-457 discloses a mechanism having a guide member forming apart of a driver guide. When a fastener has been jammed within a fastener drive track formed in the driver guide, the guide member is moved open the fastener guide track by a strong force produced by the jammed fastener.
However, with the above conventional mechanisms, an operator can manually move the guide member to open or close the fastener drive track during driving operation of a driver. For example, in case that these mechanism have been applied to a pneumatic fastener driving device which is drive by compressed air as a drive source, a problem is caused that the driver may be driven through activation of a trigger valve when the operator is manually moving the guide member from the closing position to the opening position or vice versa.
Further, the guide member is required to be held at the closing position during driving operation, and the guide member is held at the closing position normally by resilient biasing means to force the guide member in engagement with the driver guide. Although the closing position can be reliably held by increasing the biasing force of the resilient biasing means, it becomes difficult to manually move the guide member against the biasing force and therefore, the guide member must be operated by using an appropriate tool.